There is a link between leg pain (including nocturnal leg pain) and vitamin B12 deficiency. Peripheral neuropathy happens when your nerves aren't working properly and can occur when there are low levels of vitamin B12 in your body, MedlinePlus reports. It might feel like muscle cramps or simply deep leg pain, numbness, or tingling. Cramps or pain associated with B12 deficiency-related neuropathy can happen any time of day -- or just at night.
Supplementing With B12
The American Family Physician says vitamin B12 complex may be helpful in treating some patients with nocturnal leg cramps. Likewise, neuropathy due to B12 deficiency can be treated and sometimes cured, says Cleveland Clinic. A 2011 study published in Nutrition Research and Practice says some studies show vitamin B complex supplements help improve nocturnal leg cramps. However, not all cases of neuropathy can be reversed (some end up being permanent). If that's the case, neuropathy treatment may involve managing pain in addition to correcting nutrient deficiencies. The sooner neuropathy related to vitamin B12 deficiency is discovered and treated, the better your odds of repairing nerve damage.
How Much to Take
Get plenty of vitamin B12 in your diet by eating B12-rich foods and taking a multivitamin supplement containing vitamin B12 to ensure you're meeting the daily recommended dietary allowance (RDA), which is 2.4 micrograms for adult men and women. Foods rich in vitamin B12 include:
- Fish and seafood (shellfish)
- Beef liver
- Dairy foods (milk, yogurt and cheese)
- Vitamin B12-fortified breakfast cereals
Look for multivitamin supplements that meet the vitamin B12 RDA. Your doctor will likely recommend you take higher doses of oral B12 supplements if you're deficient in B12 or have you receive vitamin B12 injections.
According to a 2013 study published in Neurologic Clinics, common B12 deficiency treatment regimens include 1,000 micrograms of B12 injections daily for 5 to 7 days followed by 1,000 micrograms on a monthly basis, or B12 injections once weekly for four weeks followed by monthly injections.
Who's at Risk for B12 Deficiency?
You're at risk for B12 deficiency if you avoid animal foods (meat, fish, poultry and dairy foods), as these foods are the main sources of vitamin B12. You're also at risk if you have a health condition that doesn't allow your body to properly absorb vitamin B12, as is the case for people with pernicious anemia who lack sufficient intrinsic factor (needed for your body to properly absorb B12), and people who've had weight loss surgeries or other surgeries involving removal of parts of the digestive tract.
Other Deficiencies That May Cause Nocturnal Leg Cramps
In addition to vitamin B12 deficiency, other nutrient imbalances can cause nocturnal leg cramps or pain associated with neuropathy. According to Cleveland Clinic, these include:
- Vitamin B9 (folate)
- Vitamin B6
- Vitamin B3 (niacin)
- Vitamin B1 (thiamin)
- Vitamin E
When to See a Doctor
Always check with your doctor if you're experiencing leg cramps or leg pain regularly (whether at night or during the day), to find out the cause. Nutrient deficiencies are just one of many health conditions linked with nocturnal leg cramps and leg pain associated with neuropathy; other causes include having medical conditions (like hypothyroidism, diabetes or Parkinson's disease), taking certain medications, dehydration, pregnancy and alcoholism, says Cleveland Clinic. Poor sleep is also associated with nocturnal leg cramps, says the 2011 review published in Nutrition Research and Practice.